Question

How did the open door policy help prevent any one nation from monopolizing trade with China

Answer 1

The main way in which the Open Door Policy helped prevent any one nation from monopolizing trade with China is that it was formed an agreement between China, the US, and other European powers in which every entity agreed to trade equally and fairly with all involved. 

Answer 2

The treaty guaranteed equal trade agreements with European countries and the US.

The Open Door Policy was announced by the US as interest was increasing in China. The goal of the policy was to ensure China remained a sovereign nation but also gave each country an equal opportunity to trade with China. Great Britain, France, Germany, Russia, and Japan agreed to the policy and it was widely accepted in the US as a means of a negotiating economic foreign policy in Asia. This agreement ensured China would not be divided into many colonial segments.